Have a large code, Fortran/CC, Linux. What options can be used to maximize the computatational consistnency between the cpu's. Basically we compile/run on two different machines one with AMD and one with Intel CPUs and get slightly different answers in some fields, most are identical. Suspect this is due to rounding/thresholding (>0.5 do A else do B) Are there optimized math libraries used for Intel cpus? etc. Any compile options we could use to force maximum compatibility?
We compile now with -O0 on both. Using 14.0.1.
Would different versions of CentOS result in differences due to any changes in GCC installed on the machine?
Thanks.